Refrigerating machine



Oct. 16 .1923.

c. 1-1. HAPGOOD REFRIGERATING MACHINE Filed A1192. ll 1919 8 Sheets-Sheet 1 War 5111/1 21) REFRI GERATING MACHINE Filed Aug. 11, 1919 8 Shee ts-Sheet 2 552% f KW Oct. 16 1923. 1,471,125

c. H. HAPGOOD REFRIGERATING MACHINE Filed Aug. 11, 1919 8 Sheets-Sheet 3 fHHllllIll Oct. 16 1923. 1,471,125

c. H. HAPGOOD REFRIGERATING MACHINE Filed m. 11, 1919 8 Sheets-Sheet 4 Oct. 16 1923.

C. H. HAPGOOD REFRIGERATING MACHINE Filed Aug. 11, 1919 8 Sheets-Sheet 5 Oct. 16 1923.

C. H. HAPGOOD REFRIGBRATING MACHINE Fileci Aug. 11, a Sheets-Sheet 8 SheetsSheet C. H. HAPGOOD REFRIGERATING MACHINE Filed Aug. 11

Oct. 16 1923.

95 Swen m1 Oct. 16, 1923. 1,471,125

c. H. HAPGOOD REFRIGERATING MACHINE Filed Aug. 11, 1919 8 Sheets-Sheet 8 513 g; 56 .g 52 29 T I i v i l Q r I Hi. n

v I i a. l i 33 I 1 X 1* f 31 J0 60 A I, 63 .5 I v J1: I 7

I v v; I M N .29 J8 1 Patented Oct. 16, 19.23.

UNITED STATES PATENT OFFICE.

CYRUS H. HAPGOOID, OF NE -V YORK, N. Y., ASSIGNOB TO GEORGE P. CARROLL, OF HARTFORD, CONNECTICUT.

REFRIGERATING MACHINE.

Application filed August 11, 1919. Serial No. 316,815.

To al ti mm if on y concern:

Be it lnmwn that l. (Trans :l. lilarooon,

a citizen of the llnited States. residing at New 3. )hlt. in the county of Yew York and titate of New York have invented a new and u eful lletr' rating Machine. of which the f owing is a. specification. i ll; invention relatexto improvements in refrigerating; machines ot "the absorption type. commonly employing ammonia or formaldehyde as the refrigerant and water or some chemical as the absorbent. For simplicity. however. in the present discus sion. the figures relating to temperature and pr ure conditions. unless. otherwise specified. are to be understood as applying to machines using ammonia as the refrigerant and water as the absorbent. The purpose of my invention is to provide simple. sate. compact, inexpensive and reliable means tor the automatic operation of absorption retrigerating machines. of the intermittent or alternating type. that. with sli ht changes ot construction. may employ any kind of heating medium for the still, such as gas. steam. kerosene or electricity. The means Fo accomplishing these purposes will he hereinafter stated.

In the d rawings. Fig. l. is a dia zran'imatic re} resentatitm of my invention. showing the controlling" mechanism operatively connccted with a still. a condenser and an evaporator in circuit. it being understood that'iu practice these latter elements are subject to great variations in construction and proportioning. Fig. 2 is a plan view ol mv controlling mechanism. Fig 3 is in part a horizontal section and in part a repetition ot part oi the construction of th. preceding figure. -L is a plan view and Fig, 5 is a partial vertical section and a pa tial elevat on of a valve 65. Fig. 6 is a icr ical se tion. with some details in ele ration. of a valve (36. Fig. 'l' is a bottom view at the valve 66 with the parts 61. 90. 9:? and 93 removed. Fig. 9 is an end view of the valve (36. in part broken away and also in part in vertical section. Fig. 9 is a plan vi w of the ralve 36. Figs. 10 and 11 are realvcctivel a vert cal section. with some details in elevation. and a bottom view of a valve "(0. Fig. 12 is a section on a larger scale throu 'h the center of the valve 5 t shown in l Qdookinetoward the left,and througl'i certain parts above the valve. with,

however. certain elements shown in elevation. Fig. 13 is an enlarged plan view of the right end of a lever 29 and certain adjacent parts. Fig. ll is an enlarged front elevation. in part broken away, of certain parts shown at the right in Fig. 2.

diagrammatically indicated in Fig. 1. a still 1. also known as a generator-absorbor. ot' an approved construction, contain part of acooling water coil 2 and is partially filled with an absorbent, such as water. and in combination therewith, in varying" proportions. a refrigerant. such ammonia. In the construction shown.

the still is heated by a flame from a gas burner 3. which is ignited from time to time trom a pilot burner l. But I am not limited to any particular kind of heating means. From the still 1 a pipe 5 leads to a condenser 6, of any approved construction. which. in the construction shown. contains part 01 a cooling: water coil 7. From the condenser 6 a liquid refrigerant pipe 8 leads to an evaporator 9. also known as an ex pansion coil or chamber. which. in the construction shown. is placed in a compartment to be refrigerated 10. From the evaporator 9 a. pipe 11 leads back down into the still 1.

A. manually ope 'ated expansion valve 67 is shown as interposed at the inlet end of the evaporator 9. In parallel with the evaporator t) is a similar evaporator 72. leading from the pipe 8 to the pipe 11 and placed in a compartment 73. A thermostatically controlled expansion valve '74 is shown as interposed at the inlet end. of the evaporator T2. such valves being known in the art. The parts T2. T3 and 7+ are shown simply to indicate how my invention may be applied to a plurality of evaporators in parallel and also to a construction where the temperature in a compartment to be refrigerated is autonmticallv controlled.

lo accordance with the preferred practice. the condenser G is indicated as occupying a position above the still 1; and. in the ascending pipe 5 near its outlet into the condense interposed a non-leaking; quick action. check valve 70. to be described. Also in a cordance with the preferred practice, the pipe lfl leads downward into the lower part ot the condenser 1 and in the pipe. near to the still. is interposed a similar check valve 71. The use of check valves. so located. is' well known in the. art; but it is essential when closed.

2, is positioned sup port] ng -a.rls f s .o d. .nnnatiealiy V the'iower i'i it hand part of is to be understood that the base in any position to any conii gport. preferably near to the still in Fig. 1 and as shown in v-xtcr trousers inc; device or valve in the inlet part of the on), a sou ce of cold water e -ant transmitting device or valve 66 in; rposed in the pipe 8; a gas valve (.18 nterposed in a supply pipe lCf .-1 ae: 3. a branch of ti s pipe fr advance of the 5W 68 lo ner Al; and another water tr (.iiBVlCG or valve 69 is interposed i aver and part of the coil 7.

from the same source or" cold water s does the coil 2. These valves will scribed.

. hediaphragin shown in Fe. 3,

1 at between ups-c and low nd I l, shown in F I,

' thus formed between the parts is connected by a tu with the still 1, as indicated in :he bulb is at all times i '='1 id in the still. The l6 contains water may be of any ed construction. Secured to the unit of the housing 1 L is a spring; casing in 3.. 2 and which in turn nly secured to a foot 18 that is 'estened to the base 19, previously to. Q compression spring; 20, pcin the casing 17. surrounds a mov- "eri 2i. a d presses at the top against .22 secured to one end of the stem.

note

K The other end of the s n'ing" 2O presses against an adjustable screw-23 fitting" 1n the availed lower end of the casing l7 and anrmnznding the stern 21. The disc 22 messes against a plunger 24, the enlarged poet end of which in turn presses against El'c under side of the diaphragm I fit l phragn'i shown. in Fig. 3, .vcen upper and lower housings shown in Fins. l. and The firmly fastened to the base 19.. :het thus formed between the parts A 1 6 is r nectcd by a ti be with the eipe 5 at :2 point in advance of the valve TO.

ii l .72? 3?) shown in Figs. 1 2 and 3, cal-- ;-'io-:l h t1 c lmusinp; 5? and capable oi partial otation ahout a stud thereon. The h? or 29 carries an adjustable screw 31. which hears against a plunger 32, tending t housing 2? and the enlarged end oi hears. turn. against the under side of the diaphragm 25. A spring casing 33 :uljustably secured in a foot 34, which, in turn. is firinl fastened to the base l9. compression spring positioned in the surrounds a movable stem :36 and 7, which i l the top against a washer 3 on the small shank of the stem.

or end of the spring presses he upper end of a spring casing 38, adjustably secured to the casing d head of the stem 36 recipro- 1 the head oi" tie casing and the under surface of the left fl'tlll the position shown, tending further to compress the spring device 39, will also compr ss the Sliding and that a reverse partml rotation will be caused by the spring ice 39 only as the thrust of the spring taken up by the washer 37 hearing 'nst the head of the casing 33.

The lever 29 has a vertical slot in its right end cc 'ies a pawl 4L1, shown in Figs. 2., f l 1-, which turns on a pivot 44 supported front and back in part of the :liorzn'ng the sides of the slot. A com,-

u spring 4-2 at its left end is sup in a socket in the lever 29 to the left slot and at its right end presses t tie pawl 41-1 so as to tend to rotate it 'lockwise direction. But an arm l3. part of the pawl ll, prevents such -vond the position showm by hearing; a nst the under side of the right end ot the l ,vcr 29. A latch {15 and a forked lever 4L6, h 1 shown in Figs. 3. l2 and let, form member which turns on a stud 4:7 supported by e stud base l8 secured to the Jose 9. The extent of the rotation of the and 4:6 in a counter clockwise clicion may be regulated by an adjusting 49. which is carried by the stud base it". The construction is such that, when the lever rotates in a counter clockwise directioin the. pawl l]. engages tno latch l5 and rotates it and the forli'ed lever 46 in a clockwise direction. A continuation of such r of the lever 29 causes-the pawl 41 he end of the latch 45, at the same rim imc compressing the spring -12 and rotatarin l3 away from the lever 29, so latch and the forked lever 46 are itch to return to the position shown in the drawings. One end oi the latch d5 is fastened to the forked lever l6 by a screw 50, thus melting adjustable the position of the outer end of the latch. When the lever 29 travels back in a clockwise partial rotation, pawl t" in engages the latch 41-5, but pusl'ied in by the latch in opposition to spr ng; until it passes the end of the itch and then resumes its former position ousrqucnce oi action of the spring.

er 29 also carries a yoke 51, having and 53,'t'he volte extending backward from near the right end ot the lever valve. ti l. oli' standard construe sec red to a frame as shown 2 and 3 which, in turn, is firmly to the base it). A valve stem 56 upward through the top of the a es through the yoke "formed 7 e ends ot the forked lever t6 and may between the ends 5:2 and 53, as best shown in li s. 12- and 1;). The stem 56 t'zrlrlt's an upper collar 57 and a ower collar both heinu adjustable and so positioned that a cloclr-Xise rotation of the parts and t5 will cause the torlced lever 16 to var a inst the collar and to move the stem 1 an upward. direction. as best iI1- dicate-rl in Jigs. 2. Sand 12. Such a clockrotation of the parts l5 and 16, of s n caused by a counter clockwise rotation of the lever 29. Likewise a clockwise rotation ot the lever 29 will cause the cud-s and to hear upon the collar 57 l to move the stem 56 in a downward dircctiou. The valve 51. has an inlet port and pipe 5 branching from the suppl lezulin; to the inlet ends oi the coils 7. port and pipe (30. shown in v l. 2. 3 and is adapted to transmit 1; water under pressure, entering the valve 5-1: from tie port and pipe 59. to the valves and 6 69; a port and. pipe 6.! also so is one The valves 69 and 9 lPi struction and the valve 68 being adapted the corresponding: housing; connected with the port and pipe (30. Av plunger 75% rcciprocatcs slightly in an opening through he vertical center of the lurusiue T6 and has an enlarged part resting: on the dia- V 75. A. lohe casing 79 is secured to the h 7'6 and is provided with a valvc scat and inlet and outlet ports loading to and from the seat and severally connecting. as indicated in Fig. l. with separate parts oi the pipe 2. a stem 80 extents through the seat ot the casing 79 and carries between its ends a valve disc Sl, adapted to close the seat from above. The lower end oi the stem 80 hears down upon the plunga'cr 8 and the, upper part of the stem is surrounded above the valve disc 81 by a light spring which occupies the lower part of a section casino; 8% screwing into the top of the casing 79 and hearing upon the spring. A spring casing" 8% screws into the top ot the casino; S3 and contains a se ring; 85 rcsting' upon a lower compression i -cipher 86. which. in turru hears upon the top o the stcm 80. rm upper compression nicinhcr 8'7 bears down upon the spring 85 and is adjustahlv positioned hv a screw 88 that passes through a threaded opening: in a cap 9.) that is screwed around the top or asing 84. i

It is apparent that fluid pressure transniitt d through the port and pipe 61. and evcrtcd upward against the diaphragm 75 wi l open the valve disc F 1 and that. on a tall ot such pressure the springs 82 and R5. assisted h gravity. will close the valve dis The screw 88 is used to adjust the thrust of the SDIlUFf R 3 according to the head oi" the local water supolv.

The valve 661 alrcailv rct'errcd to coo structcd as follows: r-ihowu in Figs. 6.7. R and 9, a flexible diaphragm 90. orc'icralilv o't vanadium steel. is secured hctwvcn upper and lowcr housings ill and 95K tho lower hous ue" heiup; couucclcd with the port and p pe 6 1' pluu rcr 9 has cu enlarged part res iuuf ou th o aphrac m 9 i lever 94 is pivoted at one cud in the housiuir I l. hears ccutrallv upon the plunger 9? and at its other end has hearing upon it a iF-RW con'ipression member 95. 96 screws into an opcuiiisr near the circurp tercucc oi the housing 91 and contains a spring; 97 rcstiuo; upon the mcisihcr 95. An upper compression member 98 hears down upon the spring 97 and is adiustahlv posh tioned hv a screw 99 that passes! through a threaded openincgin a cap 10) that is screwed around the top of the casing 96. A

springca inoclose the seat from above threaded at its top and having a threaded.

lower end that asses through an op the diaphra; and screws into the 11 valve 62551115; has a valve seat and inlet and outlet ports leading to and tram the seat and severally connecting: as shown in,

Fin. with separate pa is :1: the pipe and it is bolted to the top oi. the casing 102 so as toclanip the circtunterence of the (lia; phragm 103. A stem 1% has a spider-ed lower end extent 111, 1 downward throu seat of the casing 105 and carries above spidered part valve disc 107, adapted The loiver oi? the store .106 screws into member 101 and at its 1 rounded by a light spri upon the upper surface ot the 'alve disc A cap 109, bolted to the top oil? the easi 105. bears down upon the top ot the sprin 108 and has a central socket in which the to of the stem 106 slightly reciprocates,

lt is apparent that fluid hressure transmitted through the port and pipe 01 and exerted upward against the diaphragm 00 will open the valve disc 107 and that, on a fall of such pressure, the springs 10% and 97, assisted. by gravi v, will close the valve disc. The screw 90 is used to adjust thrust of the spring: 07 according to the head of the local water supply. The oinplovu ent oil the lever 94 fulcrunied as descr icii, and. or". the two springs .100 and 07 the .attcr being adjustable, makes praeticalne a very exactadjustment of the valve 06. lt to be understood that in practice the alve 00 is positioned onlva short distance in advance of the expansion valves 07 and 741, regulating the amount at flow into the evap orators 9 and 72. res wctivelv.

The valve the valve 71 being identical therewith in construction, is constructed as follows: A flexible diaphragm 110, preterabl v ot vanadium steel, is secured between upper and lower housings 1.11 and 1112. The housing 112 is in the line 01' the pipe 5 and has a inlet port 113 at one side, an outlet port 111 from its under side and a valve seat 115 between the ports. A valve member 116 has an enlarged lower end adapted tor closing, the seat.- 115; it passes through a central opening in the diaphragm 110; it has a threaded section above the diaphragm; it has an upper end of reduced diameter; and it has a small vertical opening 117 from end to end in axial alinement with the seat plate 11:) surrounds the valve member 110 a .phragm 110 and presses upon :20 surrcuinding the valve member at the oint between it and the diaphragm. i1 nut 121 and a lock nut 122, screwed ot the valve 116, 118, 120

around the tlufeaded section member 1.10 clams the parts l V together. A. light spring is the upper end of the valve 1 a and rests upon the part sur- 1 the nut A 15 slret 1121 rests the circumlerencc ot the diaphragm ed rim of the housing; 112

0 within the r and is pressed down by a follower 125. The

liousu j 111 is bolted to the housino' 112 and threaded bolts 126 screwed down through 1, in the housing 111 so as An :teinally threadeil adjusting: member 127, i on top, may be screwed up or down ded opening in the top of the .1 so as to bear down upon the i i thus causing a greater or less e sion ot the spring as n'iay be desired. The extreme top of the valve member 116 reciproeates slightly in a cylindrical slot in the member 121 and has in the vicinity of the 123 radial openings 128. A removable rap 129 encloses the top of the housing over the member 127. is apparent that, it the valve member is closed, fluid entering the port 113, le pressure somewhat in excess of the ssure exerted in the vicinity of the port will bear upward against the dialragm 110 so as to open the valve member 7. and to compress the spring; 123, But 121 t oi": the fluid in the viiinitv oil the seat [1 passes upward through the openings 1 d 128 and tends to equalize the presurc above and below the diaphragm 110. lnder these conditions, the spring 123, with its tension adjusted by the member 127, tends to seat the valve member 116. This tendency, however, is overcome so long as the pressure oi: the fluid entering the port 113 exceeds the pressure of the fluid passing through the port 11-1, by a difference determined by the thrust oi the spring 123. But finally, under the coiulitions that arise from time to time in the operation 01 an intermittent or alternating absorption retrigerail-inn" machine, the pi issure ot the tluid enlei-ingthe port 1.13 will no longer increase, nd, as such pressure tends to equal the ressure 0; the fluid passing through the wort 11 1', tie valve member 110, acted upon the spring 123 will tightly close. The valve thus fully meets the requirements of.

ec valve in this machine The method 01 operation is as follows: lVith, the parts in the positions shown, water,

under pressure from the mains, has passed through the port and pipe 59, the valve 5 1 and the port and pipe 61 to the valves 65 and .66, causing them to be open and severally to transmit cooling water through the coil 2 to the still 1 and to transmit liquid refrigerant through the pipe 3 to the valves 67 and 7 1 into the evaporators 9 and 72. From the evaporator-s 9 and 72 the expanded refrigerant passes through the pipe 11 and the valve "It, which is open under the pressure of the incoming gas, into the still 1, where it is absorbed by the absorbent therein. The heat of absorption is carried away by the water flowing through the coil 2. In other words, the machine is in the absorption period with the compartments 10 and 73 being refrigerated by the vaporization of refrigerant in the evaporators 9 and 72. The length of the absorption period, or period of active refrigeration, depends upon the quantity of refrigerant in the condenser 6 and upon the quantity of heat that has to be taken up in the compartments 10 and 73 per unit of time. Frequently the parts are so proportioned that this period may last from twentyd'our hours to a week. Finally, however, the absorbent in the still 1 approaches a saturation limit such that it no longer can economically absorb any more expanded refrigerant. Throughout the absorption period, it is to be noted, the excess of pressure in the condenser 6 over the pressure in the still 1 has kept the valve '70 closed. Now consider especially Figs. 3, 12 and 141. The pressure in the still 1, rising gradually as the absorption eriod progresses notwithstanding the coo ing efl'ect of the Water fiowmg through the coil 2, is transmitted through the pipe 5 and the tube 28 to the diaphragm 25 so as to act on the plunger 32'and the screw 31 in such a way as to rotate the lever 29 counter clockwise, thus compressing the spring 35 and the spring device 39. This rotation of the lever 29, transmitted through the pawl 11 to the parts 45 and 16, causes the lever 16 to move the collar 58, the stem 56 and the pistons 63 and 64: in an upward di' rection. As this movement progresses. the piston 6 1 will cover the associated passage of the port and pipe 61 and later the piston 63 will cover the associated passage of the port and pipe 60. When a predeteru'iined pressure is reached, say 30 pounds gage, the piston 61- will open the port and plpe to the discharge port and pipe 62, thus relieving the pressure on the diaphragms of the valves 65 and 66 and causing them to close. At approximately the same time the piston 63 will open the port and pipe 60 to the water supply from the port and pipe 59 and will llo th water pressure to act on the valves 68 and 69, causing them to open and severally to transmit gas to the burner 3 and to transmit coooling water through the coil 7 to the condenser 6.. A change is thus effected from the absorption to the heating period. .ss the heating period begins, the valve 71 closes and the valve soon thereafter opens.

As the heating period progresses, the pressure against the diaphragm 25 increases, causing the lever 25 to continue its partial rotation in a counter clockwise direction until the ports and pipes 61 and 60 are wide open, at which time further rotation is stopped by the enlarged part of the plunger 32 coming in contact with the housing 27. As the heating period further continues, the temperature of the liquid in the still 1 gradually rises to a predetermined limit, say 300 degrees F. This rising temperature is communicated to the water in the bulb 16. As the temperature approaches 390 degrees, the pressure of thesteam in the bulb 16 approaches 52 pounds gauge; and this increasing pressure, acting through the tube 15 on the diaphragm 12, causes the plunger 2-11- to compress the spring 20 and to move the stem 1 in a downward direction. The lower end of the stem 21 then bears down upon the top of the stem 56 and moves that in the same direction, gradually causing the piston 63 to cover the associated passage of the port and pipe 60 and finally, when 300 degrees is reached, to open the port and pipe 60 to the discharge port and pipe 62, thus relieving the pressure on the diaphragms of the valves 68 and 69 and causing them to close. The heating period is now ended and the'period in which the still 1 cools down by radiation now begins. As the heating ended,the valve 70 closed. The construction of the standard valve 54:, with its operation as above described, is so well known in the art as to require no further explanation.

As the still 1 cools down, the pressure therein drops to such a point that the tie creased pressure on the diaphragm 25 allows the spring 35 and the spring device 39 to rotate the lever 29 in a clockwise direction. Such rotation causes the pawl 11 to slide by the end of the latch 15 and then the washer 37 comes in contact with the plug in the end of the casing A continued rotation, therefore, of the lever 29 is caused solely by the spring device 39. As the pressure in the still 1 drops still further, the lever 29 continues to rotate in a clockwise direction under the action of the spring device 39; and the ends 52 and 53 bear down upon the collar 57 and move the stem 56 and the pistons 63 and 6 1 still further in a downward direction. When a predetermined pressure is reached in the still 1, say atmospheric. the piston 641 opens the port and pipe 61 to the water supply,.thereb v again opening the valves 65 and 66. A change from the cooling down period to the absorption period is thus effected and the cycle of operation is complete. The valve 71 opens lot) while the pressure in the still 1 drops below the pressure in the evaporators 9 and 72.

It will. be noted that the supply of cooling water to the still 1 will yet further temporarily lower the pressure therein and cause a further opening of the port and pipe 61.

A. cessation of the flow from the source of water supply will suspend the operation o a the machine. It will be noted, also. that the pressure in the parts 16, 15, 13 and 12, at the end of the heating period acts positively through parts in alinement with one another to relieve the pressure in the devices 88 and 69 and to permit the springs therein to act. A safety valve is also innicated in Fig. 1 connected with the still 1.

In case, instead of ammonia, formaldehyde is employed, with water as the absorbent, brass and copper may be used in the refrigerant circuit and the apparatus may be designed in view of the following properties of that refrigerant:

The boiling point at 76 pounds gauge presF-aure is 90 degrees F; the pores: tage o.. the refrigerant in the weak liquor by Weight at 76 pounds gauge pressure and 320 degrees F. is 16d; the specific heat of the liquor is .921; the I). t. u. heat of dissociation per pound 31.5; the boiling point at (3 pounds gauge pressure is 12 degrees F.; the percentttjljo of the refrigerant in the strong liquor by weight at 12 pounds gauge pressure and 90 degrees F. is 42; the t. u. heat of absorption per pound is 803; and the latent heat of vaporization at 6 pounds gauge pressure is 250. The non-inflammability of formaldehyde, its low working pressures and its adaptability for use with brass and copper make it especially available as the refrigerant in very small machines.

hat I have invented and what I desire to have protected by Letters Patent ex pr seed in claims as follows.

I claim:

1. In an absorption refrigerating apparatus inc uding a still, a condenser and an evaporator in circuit, a first device for transmitting cooling Water to the sti a "7 second device for transmitting the refrigerant from the condenser into the evaporator, a third device for supplying a heating *ium to the still, a fourth device for .mitti: cocling water to the condenser. a valve communicating with said devices, and means at a high pressure limit n the still actuating the valve to transmit fluid to suspend the operation of the first and second devices and to operate the third and fourth devices, at a high temperature imit in the sti l actuating the valve to a sniit fluid to sus 'iend the operation of he th rd and fourth devices and upon a oo ing down of the still actuating the valve to transmit fluid to operate the first and second devices.

2. In an absorption refrigerating apparatus including a still, a condenser and an evaporator in circuit, a first device for transmitting cooling water to the still, a second device for transmitting the refrigerant from the condenser into the evaporator, a third (lGVllQ for supplying a heating medium to the still, a fourth device for transmitting cooling water to the condenser, and means at a high. pressure limit in the still transmitting fluid to suspend the operation of the first and second devices and to operate the third and fourth devices, at a high temperature limit in the still transmitting fluid to suspend. the operation of the third and fourth devices and upon a cooling down of the still transmitting fluid to operate the first and second devices.

3. In an absorption refrigerating apparatus including a still, a condenser and an evaporator in circuit, a first device for transmitting cooling Water to the still, a second device for transmitting the refrigerant from the condenser into the evaporator, a third device for supplying a heating medium to the still, a fourth device for transmitting cooling water to the condenser, and means controlled by temperature and pressure con ditions in the still for transmitting fluid to operate said devices to absorb expanded refrigerant from the evaporator, to expel ab sorbed refrigerant into the condenser and to transn'iit condensed refrigerant into the evaporator.

a. In an absorption refrigerating apparatus including a still, a condenser and an evaporator in circuit, means for transmitting refrigerant from the condenser into the evaporator, means for supplying a heating medium to the still, means for supplying cooling water to the still when absorbing and to the condenser when condensing, and means controlled by temperature and pressure conditions in the still to transmit fluid to operate the former means to absorb expanc ed refrigerant from the evaporator, to

expel absorbed refrigerant into the condenser and to transmit condensed refrigerant into the evaporator.

5. In an absorption refrigerating apparatus including a still, a condenser and an evaporator in circuit, means for transmitting refrigerant from the condenser into the evaporator, means for supplying a heating medium to the still, means for transmitting from a source of water supply cooling water to the still when absorbing and to the condenser when condensing, and means controlled by temperature and pressure conditions in the still to transmit water from such source to operate the former means to absorb expanded refrigerant from the evaporator, to expel absorbed refrigerant into the condenser and to transmit condensed refrigerant into the evaporator.

6. In an absorption refrigerating apparatus including a still, a condenser and an evaporator in circuit, and means controlled by temperature and pressure conditions in the still for transmitting fluid to cause the still to absorb expanded refrigerant from the evaporator and to expel absorbed refrigerant into the condenser and to cause the transmission of condensed refrigerant into the evaporator.

7. In an absorption refrigerating apparatus including a still, a condenser and an evaporator in circuit, and means controlled by temperature and pressure conditions in the still for transmitting water from a source of Water supply to cause the still to absorb expanded refrigerant. from the evaporator and to expel absorbed refrigerant into the condenser and to cause the transmission of condensed refrigerant into the 20 evaporator.

CYRUS H. HAPGOOD.

Witnesses Gnnrnonn BURGNER, Lorns S. R1011. 

